Signal transceiving module

ABSTRACT

A signal transceiving module includes: a first antenna; a first signal port; and a first processing circuit coupled to the first signal port and arranged to detect a first signal quality of a first received signal received from the first signal port and determine if the first antenna is coupled to the first signal port correctly according to at least the first signal quality.

BACKGROUND

The present invention relates to a signal transceiving module, and moreparticularly to a signal transceiving module capable of determining ifan antenna is coupled to a signal port correctly.

In a wireless communication system, the antenna is coupled to the poweramplifier (PA) of the transmitter when the wireless transceiver performsthe operation of transmitting signals, and the antenna is coupled to thereceiver (e.g., a low-noise amplifier of the receiver) when the wirelesstransceiver performs the operation of receiving signals. Therefore, theantenna is controlled to connect to the transmitter or the receiver whenthe wireless transceiver is under normal operation. Usually, the antennais externally coupled to the main circuit of the wireless transceiver.If the antenna is not coupled to the main circuit of the wirelesstransceiver correctly in the manufacturing process, such as in caseswhere the antenna is only partially connected to the main circuit orcompletely disconnected from the main circuit, then the radio frequencysignal may not be able to be received by the receiver or only a partialpower of the radio frequency signal can be received. Furthermore, thepre-transmitted signal generated by the power amplifier of thetransmitter may also not be able to be transmitted to the antenna oronly a partial pre-transmitted signal can be transmitted. Moreseriously, the entire or a partial pre-transmitted signal generated bythe transmitter may be reflected to the power amplifier and mayconsequently burn out the power amplifier or deteriorate its performanceif the reflected power is large enough. Therefore, providing a mechanismfor protecting the power amplifier from burning out when the antenna isnot coupled correctly to the main circuit of the wireless transceiverhas become an important issue in the field of wireless communicationsystems.

SUMMARY

One of the objectives of the present embodiment is to provide a signaltransceiving module capable of determining if an antenna is coupled to asignal port correctly.

According to an embodiment of the present invention, a signaltransceiving module is disclosed. The signal transceiving modulecomprises a first antenna, a first signal port, and a first processingcircuit. The first processing circuit is coupled to the first signalport and is arranged to detect a first signal quality of a firstreceived signal received from the first signal port and determine if thefirst antenna is coupled to the first signal port correctly according toat least the first signal quality.

These and other objectives of the present invention will no doubt becomeobvious to those of ordinary skill in the art after reading thefollowing detailed description of the preferred embodiment that isillustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating a signal transceiving module accordingto a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a signal transceiving module accordingto a second embodiment of the present invention.

FIG. 3 is a diagram illustrating a signal transceiving module accordingto a third embodiment of the present invention.

FIG. 4A in conjunction with FIG. 4B is a flowchart illustrating amonitoring method performed by the signal transceiving module of FIG. 3according to an embodiment of the present invention.

FIG. 5 is a diagram illustrating a power protection scheme performed bythe signal transceiving module of FIG. 3 according to an embodiment ofthe present invention.

FIG. 6 is a timing diagram illustrating a data frame received andtransmitted by the signal transceiving module of FIG. 3 according to anembodiment of the present invention.

FIG. 7 is a diagram illustrating a signal transceiving module accordingto a fourth embodiment of the present invention.

FIG. 8A in conjunction with FIG. 8B is a flowchart illustrating amonitoring method performed by the signal transceiving module of FIG. 7according to an embodiment of the present invention.

FIG. 9 is a flowchart illustrating a transmitted power differencechecking method performed by the signal transceiving module of FIG. 7according to an embodiment of the present invention.

FIG. 10 is a diagram illustrating a power protection scheme performed bythe signal transceiving module of FIG. 7 according to an embodiment ofthe present invention.

FIG. 11 is a timing diagram illustrating a data frame received andtransmitted by the signal transceiving module of FIG. 7 according to anembodiment of the present invention.

DETAILED DESCRIPTION

Certain terms are used throughout the description and following claimsto refer to particular components. As one skilled in the art willappreciate, electronic equipment manufacturers may refer to a componentby different names. This document does not intend to distinguish betweencomponents that differ in name but not function. In the followingdescription and in the claims, the terms “include” and “comprise” areused in an open-ended fashion, and thus should be interpreted to mean“include, but not limited to . . . ”. Also, the term “couple” isintended to mean either an indirect or direct electrical connection.Accordingly, if one device is coupled to another device, that connectionmay be through a direct electrical connection, or through an indirectelectrical connection via other devices and connections.

Please refer to FIG. 1. FIG. 1 is a diagram illustrating a signaltransceiving module 100 according to a first embodiment of the presentinvention. The signal transceiving module 100 comprises an antenna 101,a signal port 102, a power amplifying circuit 103, a first processingcircuit 104, a second processing circuit 105, and a switching circuit106. The first processing circuit 104 is coupled to the signal port 102and arranged to detect a signal quality of a received signal Silreceived from the signal port 102 and determine if the antenna 101 iscoupled to the signal port 102 correctly according to at least thesignal quality. The power amplifying circuit 103 is coupled to thesignal port 102 and arranged to generate a transmitting signal when thesignal transceiving module 100 is under the transmitting mode. Thesignal quality of the received signal Sil can be a received signalstrength indication (RSSI), a physical carrier tointerference-plus-noise ratio (PCINR), or a signal-to-noise ratio (SNR)of the first received signal.

In this embodiment, the first processing circuit 104 may be a receiverand the second processing circuit 105 may be a transmitter. When thesignal transceiving module 100 is under the receiving mode, the firstprocessing circuit 104 detects if the signal quality is lower than apredetermined quality level, and the first processing circuit 104determines that the antenna 101 is not coupled to the signal port 102correctly when the signal quality is lower than the predeterminedquality level. Then, when the first processing circuit 104 detects thatthe antenna 101 is not coupled to the signal port 102 correctly and thepower amplifying circuit 103 is not to be used in a normal operation(e.g., the transmitting mode) of the signal transceiving module 100, thefirst processing circuit 104 stops the first power amplifying circuit103 from generating the transmitting signal St. When the firstprocessing circuit 104 detects that the antenna 101 is not coupled tothe signal port 102 correctly and the power amplifying circuit 103 is tobe used in a normal operation (e.g., the transmitting mode) of thesignal transceiving module 100, the first processing circuit 104 limitsa maximum power of the transmitted signal St1 to a predetermined powerlevel. Therefore, the switching circuit 106 is utilized to couple theantenna 101 to the first processing circuit 104 for receiving thereceived signal Si, or couple the antenna 101 to the power amplifyingcircuit 103 for transmitting the transmitted signal St.

In addition, when the first processing circuit 104 detects that thesignal quality is higher than a predetermined quality level, the firstprocessing circuit 104 determines that the antenna 101 is coupled to thesignal port 102 correctly. In this case, the first processing circuit104 stops detecting the signal quality of the received signal Si. Itshould be noted that, when the antenna 101 is coupled to the signal port102 correctly (i.e., the impedance at the signal port 102 is matched),the power of the received signal Sil can be transmitted to the firstprocessing circuit 104 without loss (or within an acceptable range ofloss), and the power of the transmitted signal St1 can be transmitted tothe antenna 101 without reflection (or within an acceptable range ofreflection). When the antenna 101 is not coupled to the signal port 102correctly (i.e., the impedance at the signal port 102 is not matched),e.g., the cases where the antenna 101 is only partially connected to orimproperly connected to the signal port 102 or completely disconnectedfrom the signal port 102, the power of the received signal Sil may notbe transmitted to the first processing circuit 104 with an acceptablepower, and the power of the transmitted signal St1 may not be totallytransmitted to the antenna 101, consequently causing power to bereflected to the power amplifying circuit 103. Therefore, by controllingthe power amplifying circuit 103 to stop generating the transmittingsignal St1, or limiting the maximum power of the transmitted signal St1to the predetermined power level when the first processing circuit 104detects that the antenna 101 is not coupled to the signal port 102correctly, the power amplifying circuit 103 can be prevented fromburning out or deterioration.

Please refer to FIG. 2. FIG. 2 is a diagram illustrating a signaltransceiving module 200 according to a second embodiment of the presentinvention. The signal transceiving module 200 comprises an antenna 201,a signal port 202, a power amplifying circuit 203, a first processingcircuit 204, a second processing circuit 205, a switching circuit 206,and a power detector 207. In this embodiment, the switching circuit 206is arranged to selectively couple the signal port 202 to the firstprocessing circuit 204 (e.g., a receiver) or the power amplifyingcircuit 203, wherein the first processing circuit 204 determines if theantenna 201 is coupled to the signal port 202 correctly as described inthe first embodiment (i.e., the signal transceiving module 100), andwhen the first processing circuit 204 determines that the antenna 201 isnot coupled to the signal port 202 correctly, the switching circuit 206couples the signal port 202 to the power amplifying circuit 203. Thesecond processing circuit 205 (e.g., a transmitter), which is coupled tothe power amplifying circuit 203, is arranged to control the poweramplifying circuit 203 to output the transmitting signal St2 having afirst predetermined power level to the signal port 202 when the poweramplifying circuit 203 is coupled to the signal port 202.

The power detector 207, which can be a low-pass filter coupled to thesecond processing circuit 205 and a square law unit and the square lawunit further coupled to the signal port 202, is arranged to detect apower level at the signal port 202 when the power amplifying circuit 203outputs the transmitting signal St2. The second processing circuit 205further determines if the power amplifying circuit 203 is coupled to theantenna 201 correctly according to a power difference between the powerlevel of the transmitting signal St2 and the first predetermined powerlevel. When the second processing circuit 205 detects that the powerdifference is not larger than a predetermined power difference level,the second processing circuit 205 determines that the power amplifyingcircuit 203 is coupled to the antenna 201 correctly. Then, the secondprocessing circuit 205 stop determines if the power amplifying circuit203 is coupled to the antenna 201 correctly.

When the second processing circuit 205 detects that the power differenceis larger than the predetermined power difference level, the secondprocessing circuit 205 determines that the power amplifying circuit 203is not coupled to the antenna 201 correctly. In this case, if the poweramplifying circuit 203 is not to be used in a normal operation (e.g.,the transmitting mode) of the signal transceiving module 200, the secondprocessing circuit 205 further stops the power amplifying circuit 203from generating the transmitting signal St2. If the power amplifyingcircuit 203 is to be used in the normal operation of the signaltransceiving module 200, the second processing circuit 205 furtherlimits a maximum power of the transmitting signal St2 to a secondpredetermined power level. It should be noted that, in this embodiment,the signal transceiving module 200 is controlled to double check if theantenna 201 is coupled to the signal port 202 correctly by detecting thereceived signal Sit and detecting the transmitted signal St2 for moreprecisely determining the connecting condition of the antenna 201. Then,by controlling the power amplifying circuit 203 to stop generating thetransmitting signal St2, or limiting the maximum power of thetransmitted signal St2 to the second predetermined power level when thesecond processing circuit 205 detects that the antenna 201 is notcoupled to the signal port 202 correctly, the power amplifying circuit203 can be prevented from burning out or deterioration.

Please refer to FIG. 3. FIG. 3 is a diagram illustrating a signaltransceiving module 300 according to a third embodiment of the presentinvention. The signal transceiving module 300 comprises a first antenna301, a second antenna 302, a first signal port 303, a second signal port304, a first power amplifying circuit (PA1) 305, a second poweramplifying circuit (PA2) 306, a first processing circuit 307, a secondprocessing circuit 308, a first switching circuit 309, and a secondswitching circuit 310. The signal transceiving module 300 may be amulti-input-multi-output (MIMO) transceiving system, wherein themulti-input-multi-output transceiving system comprises a plurality ofantennas. The first switching circuit 309 is arranged to selectivelycouple the first signal port 303 to the first processing circuit 307 orthe first power amplifying circuit 305. The second switching circuit 310is arranged to selectively couple the second signal port 304 to thefirst processing circuit 307 or the second power amplifying circuit 306.

When the signal transceiving module 300 is turned on, the firstswitching circuit 309 is controlled to couple the first signal port 303to the first processing circuit 307, and the second switching circuit310 is controlled to couple the second signal port 304 to the firstprocessing circuit 307. The first processing circuit 307 is arranged todetect a first signal quality of a first received signal Si3 a receivedfrom the first signal port 303 and detect a second signal quality of asecond received signal Si3 b received from the second signal port 304 todetermine if the first antenna 301 and the second antenna 302 arerespectively coupled to the first signal port 303 and the second signalport 304 correctly according to the first and second signal quality. Inthis embodiment, a parameter PA_overload is defined to determine if apower protection scheme should be operated. More specifically, when thePA_overload is 1, the power protection scheme should be operated, andwhen the PA_overload is 0, the signal transceiving module 300 can beoperated normally.

Please refer to FIG. 4A and FIG. 4B. FIG. 4A in conjunction with FIG. 4Bis a flowchart illustrating a monitoring method 400 performed by thesignal transceiving module 300 according to an embodiment of the presentinvention. Provided that substantially the same result is achieved, thesteps of the flowchart shown in FIG. 4A and FIG. 4B need not be in theexact order shown and need not be contiguous; that is, other steps canbe intermediate. The signal transceiving module 300 executes themonitoring method 400 to determine if the first antenna 301 and thesecond antenna 302 are respectively coupled to the first signal port 303and the second signal port 304 correctly. The monitoring method 400comprises the following steps:

Step 401: Power on;

Step 402: Set the initial parameters rx_cnt=0, rx1_dis_cnt=0, andrx2_dis_cnt=0;

Step 403: Receive a data frame via the first antenna 301 and the secondantenna 302;

Step 404: Determine if RSSI_rx1<RSSI_dis_th and RSSI_rx2<RSSI_dis_th; ifyes, go to step 405, if no go to step 409;

Step 405: Determine if PCINR_rx2−PCINR_rx1>PCINR_diff_th andPCINR_rx1<PCINR_dis_th; if yes, go to step 406, if no, go to step 407;

Step 406: Perform the operation of rx1_dis_cnt++;

Step 407: Determine if PCINR_rx1−PCINR_rx2>PCINR_diff_th andPCINR_rx2<PCINR_dis_th; if yes, go to step 408, if no, go to step 413;

Step 408: Perform the operation of rx2_dis_cnt++, go to step 413;

Step 409: Determine if RSSI_rx2−RSSI_rx1>RSSI_diff_th; if yes, go tostep 410, if no go to step 411;

Step 410: Perform the operation of rx1_dis_cnt++;

Step 411: Determine if RSSI_rx1−RSSI_rx2>RSSI_diff_th; if yes, go tostep 412, if no go to step 413;

Step 412: Perform the operation of rx2_dis_cnt++;

Step 413: Perform the operation of rx_cnt++;

Step 414: Determine if rx_cnt>rx_cnt_th; if yes, go to step 415, if no,go to step 422;

Step 415: Determine if rx1_dis_cnt>rx_dis_th, if yes, go to step 416, ifno, go to step 420;

Step 416: Set the parameter PA1_overoad=1;

Step 417: Determine if rx2_dis_cnt>rx_dis_th; if yes, go to step 418, ifno, go to step 421;

Step 418: Set the parameter PA2_overoad=1;

Step 419: Reset the initial parameters rx_cnt=0, rx1_dis_cnt=0, andrx2_dis_cnt=0, go to step 422;

Step 420: Set the parameter PA1_overoad=0, go to step 417;

Step 421: Set the parameter PA2_overoad=0, go to step 419;

Step 422: End the monitoring operation.

When the signal transceiving module 300 is turned on (Step 401), thesignal transceiving module 300 sets the initial parameters rx_cnt=0,rx1_dis_cnt=0, and rx2_dis_cnt=0 (Step 402), wherein the parameterrx_cnt represents the counting number of the received downlinksub-frame, the parameter rx1_dis_cnt represents the counting number fordetermining whether the first antenna 301 is coupled to the first signalport 303 properly, and the parameter rx2_dis_cnt represents the countingnumber for determining whether the second antenna 302 is coupled to thesecond signal port 304 properly. Then, the signal transceiving module300 starts to receive a data frame via the first antenna 301 and thesecond antenna 302 (Step 403).

When the first processing circuit 307 detects that the first receivedsignal strength indication RSSI_rx1 of the first received signal Si3 aand the second received signal strength indication RSSI_rx2 of thesecond received signal Si3 b are both lower than a predetermined qualitylevel RSSI_dis_th (Step 404), the first processing circuit 307 performsa physical carrier to interference-plus-noise ratio (PCINR) checkingoperation (Step 405-408) upon the first received signal Si3 a and thesecond received signal Si3 b to check if the first antenna 301 and thesecond antenna 302 are respectively coupled to the first signal port 303and the second signal port 304 correctly. When the first processingcircuit 307 detects that at least one of the first received signalstrength indication RSSI_rx1 and the second received signal strengthindication RSSI_rx2 is not lower than the predetermined quality levelRSSI_dis_th, the first processing circuit 307 performs a received signalstrength indication (RSSI) checking operation (Step 409-412) upon thefirst received signal Si3 a and the second received signal Si3 b tocheck if the first antenna 301 and the second antenna 302 arerespectively coupled to the first signal port 303 and the second signalport 304 correctly.

More specifically, in step 405, when the first processing circuit 307subtracts the first physical carrier to interference-plus-noise ratioPCINR_rx1 of the first received signal Si3 a from the second physicalcarrier to interference-plus-noise ratio PCINR_rx2 of the secondreceived signal Si3 b to check if a difference is larger than a firstthreshold PCINR_diff_th, and to check if the first physical carrier tointerference-plus-noise ratio PCINR_rx1 of the first received signal Si3a is smaller than a second threshold PCINR_dis_th (Step 405); and whenthe difference is larger than the first threshold PCINR_diff_th and thefirst physical carrier to interference-plus-noise ratio PCINR_rx1 of thefirst received signal Si3 a is smaller than the second thresholdPCINR_dis_th, the first processing circuit 307 determines that the firstantenna 301 is not coupled to the first signal port 303 correctly. Then,the first processing circuit 307 increases the counting number of whenthe first antenna 301 is not coupled to the first signal port 303correctly by 1, i.e., rx1_dis_cnt++(Step 406). Otherwise, the firstprocessing circuit 307 subtracts the second physical carrier tointerference-plus-noise ratio PCINR_rx2 of the second received signalSi3 b from the first physical carrier to interference-plus-noise ratioPCINR_rx1 of the first received signal Si3 a to check if a difference islarger than the first threshold PCINR_diff_th, and to check if thesecond physical carrier to interference-plus-noise ratio PCINR_rx2 ofthe second received signal Si3 b is smaller than the second thresholdPCINR_dis_th (Step 407). When the difference is larger than the firstthreshold PCINR_diff_th and the second physical carrier tointerference-plus-noise ratio PCINR_rx2 of the second received signalSi3 b is smaller than the second threshold PCINR_dis_th, the firstprocessing circuit 307 determines that the second antenna 302 is notcoupled to the second signal port 304 correctly. Then, the firstprocessing circuit 307 increases the counting number of when the secondantenna 302 is not coupled to the second signal port 304 correctly by 1,i.e., rx2_dis_cnt++(Step 408).

In the received signal strength indication (RSSI) checking operation,the first processing circuit 307 subtracts the first received signalstrength indication RSSI_rx1 of the first received signal Si3 a from thesecond received signal strength indication RSSI_rx2 of the secondreceived signal Si3 b to check if a difference is larger than athreshold RSSI_diff_th (Step 409); when the difference is larger thanthe threshold RSSI_diff_th, the first processing circuit 307 determinesthat the first antenna 301 is not coupled to the first signal port 303correctly. Then, the first processing circuit 307 increases the countingnumber of when the first antenna 301 is not coupled to the first signalport 303 correctly by 1, i.e., rx1_dis_cnt++ (Step 410). Otherwise, thefirst processing circuit 307 subtracts the second received signalstrength indication RSSI_rx2 of the second received signal Si3 b fromthe first received signal strength indication RSSI_rx1 of the firstreceived signal Si3 a to check if a difference is larger than thethreshold RSSI_diff_th (Step 411); and when the difference is largerthan the threshold RSSI_diff_th, the first processing circuit 307determines that the second antenna 302 is not coupled to the secondsignal port 304 correctly. Then, the first processing circuit 307increases the counting number of when the second antenna 302 is notcoupled to the second signal port 304 correctly by 1, i.e.,rx2_dis_cnt++ (Step 412).

In step 413, the first processing circuit 307 increases the countingnumber of the received downlink sub-frame by 1, i.e., rx_cnt++ (Step413). When the number rx_cnt of the received downlink sub-frame isgreater than a threshold rx_cnt_th (Step 414 in FIG. 4B), the firstprocessing circuit 307 performs the PA overload checking operation (Step415-419) to check if the first power amplifying circuit 305 and thesecond power amplifying circuit 306 are possibly overloaded. Onepossibility is PA could be overloaded due to the antenna is notconnected properly. More specifically, the first processing circuit 307determines if the counting number rx1_dis_cnt of the first antenna 301is possible not coupled to the first signal port 303 is greater than athreshold rx_dis_th (Step 415). When the counting number rx1_dis_cnt isgreater than the threshold rx_dis_th, the first processing circuit 307determines that the first power amplifying circuit 305 may beoverloaded, and sets the parameter PA1_overload as 1 (Step 416).Otherwise, the first processing circuit 307 determines that the firstpower amplifying circuit 305 is not overloaded, and sets the parameterPA1_overload as 0 (Step 420).

Then, the first processing circuit 307 determines if the counting numberrx2_dis_cnt of the second antenna 302 is possibly not coupled to thesecond signal port 304 is greater than the threshold rx_dis_th (Step417). When the counting number rx2_dis_cnt is greater than the thresholdrx_dis_th, the first processing circuit 307 determines that the secondpower amplifying circuit 306 may be overloaded, and sets the parameterPA2_overload as 1 (Step 418). Otherwise, the first processing circuit307 determines that the second power amplifying circuit 306 is notoverloaded, and sets the parameter PA2_overload as 0 (Step 421).

When both the overload checking of the first power amplifying circuit305 and the second power amplifying circuit 306 are checked, the firstprocessing circuit 307 resets the initial parameters rx_cnt,rx1_dis_cnt, and rx2_dis_cnt as 0 (Step 419), and ends the monitoringoperation (Step 422).

In addition, according to the outcome of the overload checking upon thefirst power amplifying circuit 305 and the second power amplifyingcircuit 306, the second processing circuit 308 (which may be controlledby the first processing circuit 307) further performs the powerprotection scheme 500 to control operations of the first poweramplifying circuit 305 and the second power amplifying circuit 306according to the parameters PA1_overload PA2_overload as shown in FIG.5. FIG. 5 is a diagram illustrating the power protection scheme 500performed by the signal transceiving module 300 according to anembodiment of the present invention. Provided that substantially thesame result is achieved, the steps of the flowchart shown in FIG. 5 neednot be in the exact order shown and need not be contiguous, that is,other steps can be intermediate. The power protection scheme 500comprises the following steps:

Step 501: Start;

Step 502: Determine if the parameter PA1_overload is 1; if yes, go tostep 503, if no, go to step 505;

Step 503: Determine if the parameter OFF_PA1 is 1; if yes, go to step504, if no, go to step 506;

Step 504: Turn off the first power amplifying circuit 305, go to step508;

Step 505: Turn on the first power amplifying circuit 305, go to step508;

Step 506: Determine if txpow_tar>pw_max−pw_dw; if yes, go to step 507,if no, go to step 508;

Step 507: Set txpow_p1 as pw_max−pw_dw;

Step 508: Determine if the parameter PA2_overload is 1; if yes, go tostep 509, if no, go to step 511;

Step 509: Determine if the parameter OFF_PA2 is 1; if yes, go to step510, if no, go to step 512;

Step 510: Turn off the second power amplifying circuit 306, go to step514;

Step 511: Turn on the second power amplifying circuit 306, go to step514;

Step 512: Determine if txpow_tar>(pw_max−pw_dw); if yes, go to step 513,if no, go to step 514;

Step 513: Set txpow_p2 as pw_max−pw_dw;

Step 514: End the power protection scheme 500.

When the PA overload checking operation (Step 415-419) is performed, thesecond processing circuit 308 (which may be controlled by the firstprocessing circuit 307) checks the outcome of the parameter PA1_overloadto determine if the first power amplifying circuit 305 is overloaded(Step 502). When the first power amplifying circuit 305 is overloaded,and when the first power amplifying circuit 305 is not to be used in thenormal operation of the signal transceiving module 300, i.e., whenOFF_PA1=1, the second processing circuit 308 stops the first poweramplifying circuit 305 from generating the transmitting signal St3 a.For example, the second processing circuit 308 just turns off the firstpower amplifying circuit 305 (Step 504). However, when the first poweramplifying circuit 305 is overloaded, and when the first poweramplifying circuit 305 is to be used in the normal operation of thesignal transceiving module 300, the second processing circuit 308determines if the power txpow_tar to be transmitted by the first poweramplifying circuit 305 is larger than the predetermined power level,wherein the predetermined power level is a power level lower than themaximum power pw_max of the first power amplifying circuit 305 by apredetermined power range pw_dw, i.e., pw_max−pw_dw. When the secondprocessing circuit 308 determines that the power txpow_tar to betransmitted by the first power amplifying circuit 305 is larger than thepredetermined power level, i.e., txpow_tar>pw_max−pw_dw, the secondprocessing circuit 308 sets the maximum power txpow_p1 to be transmittedby the first power amplifying circuit 305 as the predetermined powerlevel, i.e., pw_max−pw_dw.

In addition, the second processing circuit 308 checks the outcome of theparameter PA2_overload to determine if the second power amplifyingcircuit 306 is overloaded (Step 508). When the second power amplifyingcircuit 306 is overloaded, and when the second power amplifying circuit306 is not to be used in the normal operation of the signal transceivingmodule 300, i.e., when OFF_PA2=1, the second processing circuit 308stops the second power amplifying circuit 306 from generating thetransmitting signal St3 b. For example, the second processing circuit308 just turns off the second power amplifying circuit 306 (Step 510).However, when the second power amplifying circuit 306 is overloaded, andwhen the second power amplifying circuit 306 is to be used in the normaloperation of the signal transceiving module 300, the second processingcircuit 308 determines if the power txpow_tar to be transmitted by thesecond power amplifying circuit 306 is larger than the predeterminedpower level, wherein the predetermined power level is a power levellower than the maximum power pw_max of the second power amplifyingcircuit 306 by a predetermined power range pw_dw, i.e., pw_max−pw_dw.When the second processing circuit 308 determines that the powertxpow_tar to be transmitted by the second power amplifying circuit 306is larger than the predetermined power level, i.e.,txpow_tar>pw_max−pw_dw, the second processing circuit 308 sets themaximum power txpow_p2 to be transmitted by the second power amplifyingcircuit 306 as the predetermined power level, i.e., pw_max−pw_dw.

In steps 502 and 508, when the first power amplifying circuit 305 andthe second power amplifying circuit 306 are not overloaded, the secondprocessing circuit 308 simply turns on the first power amplifyingcircuit 305 and the second power amplifying circuit 306 (steps 505 and511).

Therefore, by controlling the power amplifying circuit having an antennathat is not coupled to its signal port correctly to stop generating thetransmitting signal, or by limiting the maximum power of the transmittedsignal to the predetermined power level, the power amplifying circuitcan be prevented from burning out or deterioration.

Please refer to FIG. 6. FIG. 6 is a timing diagram illustrating a dataframe 600 received and transmitted by the signal transceiving module 300according to an embodiment of the present invention. The data frame 600comprises a receive transition gap (RTG), a downlink (DL) sub-frame, atransmit transition gap (TTG), and an uplink (UL) sub-frame. Accordingto the embodiment, the monitoring operation (i.e., the monitoring method400) is performed in a time interval T1 when the downlink sub-frame isreceived. Based on the outcome of the monitoring operation, the powerprotection scheme 500 is performed before the transmission of the uplinksub-frame, i.e., in a time interval T2 of the transmit transition gap.

Please refer to FIG. 7. FIG. 7 is a diagram illustrating a signaltransceiving module 700 according to a fourth embodiment of the presentinvention. The signal transceiving module 700 comprises a first antenna701, a second antenna 702, a first signal port 703, a second signal port704, a first switching circuit 705, and a second switching circuit 706,a first power amplifying circuit 707, a second power amplifying circuit708, a first power detector 709, a second power detector 710, a firstprocessing circuit 711, and a second processing circuit 712. The signaltransceiving module 700 may be a multi-input-multi-output (MIMO)transceiving system, wherein the multi-input-multi-output transceivingsystem comprises a plurality of antennas. The first switching circuit705 is arranged to selectively couple the first signal port 703 to thefirst processing circuit 711 or the first power amplifying circuit 707.The second switching circuit 706 is arranged to selectively couple thesecond signal port 704 to the first processing circuit 711 or the secondpower amplifying circuit 708. The first processing circuit 711determines if the first antenna 701 and the second antenna 702 arerespectively coupled to the first signal port 703 and the second signalport 704 correctly according to the first received signal Si7 a and thesecond received signal Si7 b as described in the above-mentionedembodiment (i.e., the signal transceiving module 300), and when thefirst processing circuit 711 determines that one antenna is not coupledto its signal port correctly, the corresponding switching circuitcouples the signal port to the corresponding power amplifying circuit.Then, the second processing circuit 712 (e.g., a transmitter), which iscoupled to the first power amplifying circuit 707 and the second poweramplifying circuit 708, is arranged to control the first poweramplifying circuit 707 to output the first transmitting signal St7 ahaving a first predetermined power level to the first signal port 703when the first power amplifying circuit 707 is coupled to the firstsignal port 703, and to control the second power amplifying circuit 708to output the second transmitting signal St7 b having a secondpredetermined power level to the second signal port 704 when the secondpower amplifying circuit 708 is coupled to the second signal port 704.

The first power detector 709, which is coupled to the second processingcircuit 712 and the first signal port 703, is arranged to detect a powerlevel at the first signal port 703 when the first power amplifyingcircuit 707 outputs the first transmitting signal St7 a. The secondpower detector 710, which is coupled to the second processing circuit712 and the second signal port 704, is arranged to detect a power levelat the second signal port 704 when the second power amplifying circuit708 outputs the second transmitting signal St7 b. Then, the secondprocessing circuit 712 further determines if the first power amplifyingcircuit 707 is coupled to the first antenna 701 correctly according to apower difference between the power level of the first transmittingsignal St7 a and a predetermined power level, and determines if thesecond power amplifying circuit 708 is coupled to the second antenna 702correctly according to a power difference between the power level of thesecond transmitting signal St7 b and the predetermined power level.

More specifically, when the signal transceiving module 700 is turned on,the first switching circuit 705 is controlled to couple the first signalport 703 to the first processing circuit 711, and the second switchingcircuit 706 is controlled to couple the second signal port 704 to thefirst processing circuit 711. The first processing circuit 711 isarranged to detect a first signal quality of a first received signal Si7a received from the first signal port 703 and detect a second signalquality of a second received signal Si7 b received from the secondsignal port 704 to determine if the first antenna 701 and the secondantenna 702 are respectively coupled to the first signal port 703 andthe second signal port 704 correctly according to the first signalquality and the second signal quality. Similar to the above embodiment(i.e., the signal transceiving module 300), a parameter PA_overload isalso defined to determine if a power protection scheme should beoperated. More specifically, when the PA_overload is 1, the powerprotection scheme should be operated, and when the PA_overload is 0, thesignal transceiving module 700 can be operated normally.

Please refer to FIG. 8A and FIG. 8B. FIG. 8A in conjunction with FIG. 8Bis a flowchart illustrating a monitoring method 800 performed by thesignal transceiving module 700 according to an embodiment of the presentinvention. Provided that substantially the same result is achieved, thesteps of the flowchart shown in FIG. 8A and FIG. 8B need not be in theexact order shown and need not be contiguous; that is, other steps canbe intermediate. The signal transceiving module 700 executes themonitoring method 800 to determine if the first antenna 701 and thesecond antenna 702 are respectively coupled to the first signal port 703and the second signal port 704 correctly. The monitoring method 800comprises the following steps:

Step 801: Power on;

Step 802: Set the initial parameters rx_cnt=0, rx1_dis_cnt=0, andrx2_dis_cnt=0;

Step 803: Receive a data frame via the first antenna 701 and the secondantenna 702;

Step 804: Determine if RSSI_rx1<RSSI_dis_th and RSSI_rx2<RSSI_dis_th; ifyes, go to step 805, if no go to step 809;

Step 805: Determine if PCINR_rx2−PCINR_rx1>PCINR_diff_th; if yes, go tostep 806, if no, go to step 807;

Step 806: Perform the operation of rx1_dis_cnt++;

Step 807: Determine if PCINR_rx1−PCINR_rx2>PCINR_diff_th; if yes, go tostep 808, if no, go to step 813;

Step 808: Perform the operation of rx2_dis_cnt++, go to step 813;

Step 809: Determine if RSSI_rx2−RSSI_rx1>RSSI_diff_th; if yes, go tostep 810, if no go to step 811;

Step 810: Perform the operation of rx1_dis_cnt++;

Step 811: Determine if RSSI_rx1−RSSI_rx2>RSSI_diff_th; if yes, go tostep 812, if no go to step 813;

Step 813: Perform the operation of rx2_cnt++;

Step 814: Determine if rx_cnt>rx_cnt_th; if yes, go to step 815, if no,go to step 822;

Step 815: Determine if rx_dis_cnt>rx_dis_th if yes, go to step 816, ifno, go to step 820;

Step 816: Perform the transmitted power difference checking operation;

Step 817: Determine if rx2_dis_cnt>rx_dis_th; if yes, go to step 818, ifno, go to step 821;

Step 818: Perform the transmitted power difference checking operation;

Step 819: Reset the initial parameters rx_cnt=0, rx1_dis_cnt=0, andrx2_dis_cnt=0, go to step 822;

Step 820: Set the parameter PA1_overoad=0, go to step 817;

Step 821: Set the parameter PA2_overoad=0, go to step 819;

Step 822: End the monitoring operation.

It should be noted that, as the operation of the monitoring method 800is similar to the operation of the monitoring method 400, the detaileddescription of the steps 801-822 is omitted here for brevity. Accordingto this embodiment, in step 814 in FIG. 8B, when the number rx_cnt ofthe received downlink sub-frame is greater than a threshold rx_cnt_th,the first processing circuit 711 performs the PA overload checkingoperation (Step 815-819) to check if the first power amplifying circuit707 and the second power amplifying circuit 708 are overloaded. Morespecifically, the first processing circuit 711 determines if thecounting number rx1_dis_cnt of when the first antenna 701 is not coupledto the first signal port 703 is greater than a threshold rx_dis_th (Step815). When the counting number rx1_dis_cnt is not greater than thethreshold rx_dis_th, the first processing circuit 711 determines thatthe first power amplifying circuit 707 is not overloaded, and sets theparameter PA1_overload as 0 (Step 820). Otherwise, the first processingcircuit 711 performs the transmitted power difference checking operationto further determine if the first power amplifying circuit 707 isoverloaded or not as shown in FIG. 8B (step 816). Similarly, the firstprocessing circuit 711 further determines if the counting numberrx2_dis_cnt of when the second antenna 702 is not coupled to the secondsignal port 704 is greater than a threshold rx_dis_th (Step 817). Whenthe counting number rx2_dis_cnt is greater than the threshold rx_dis_th,the first processing circuit 711 determines that the second poweramplifying circuit 708 is not overloaded, and sets the parameterPA2_overload as 0 (Step 821). Otherwise, the first processing circuit711 performs the transmitted power difference checking operation tofurther determine if the second power amplifying circuit 708 isoverloaded or not as shown in FIG. 8B (Step 818).

FIG. 9 is a flowchart illustrating a transmitted power differencechecking method 900 performed by the signal transceiving module 700according to an embodiment of the present invention. Provided thatsubstantially the same result is achieved, the steps of the flowchartshown in FIG. 9 need not be in the exact order shown and need not becontiguous; that is, other steps can be intermediate. The signaltransceiving module 700 performs the transmitted power differencechecking method 900 to further determine if the first antenna 701 andthe second antenna 702 are respectively coupled to the first signal port703 and the second signal port 704 correctly. The transmitted powerdifference checking method 900 comprises the following steps:

Step 901: Power on;

Step 902: Set the initial parameters tx_cnt=0, tx_ar_cnt=0,txpow_chk_(1,k-1)=0, txpow_chk_(2,k-1)=0, PA1_overload=0, andPA2_overload=0;

Step 903: Receive the outcomes of the monitoring method 800;

Step 904: Determine if the txpw_chk_en is 1; if yes, go to step 905, ifno, go to step 916;

Step 905: Determine if tx_cnt is tx_chk_period; if yes, go to step 906,if no, go to step 908;

Step 906: Determine txpow_diff₁ by txpow_det₁-txpow_tar, and/ordetermine txpow_diff₂ by txpow_det₂-txpow_tar, and set tx_cnt as 0;

Step 907: Determine txpow_chk_(1,k) byα·txpow_chk_(1,k-1)+(1−α)txpow_diff₁, and/or determine txpow_chk_(2,k)by α·txpow_chk_(2,k-1)+(1−α)txpow_diff₂, and perform the operation oftx_ar_cnt++, go to step 909;

Step 908: Perform the operation of tx_cnt++;

Step 909: Determine if tx_ar_cnt>tx_ar_th; if yes, go to step 910, ifno, go to step 916;

Step 910: Determine if txpow_chk_(1,k)>txpw_diff_th; if yes, go to step911, if no go to step 914;

Step 911: Set the parameter PA1_overoad=1, and go to step 912;

Step 912: Determine if txpow_chk_(2,k)>txpw_diff_th; if yes, go to step913, if no go to step 915;

Step 913: Set the parameter PA2_overoad=1, go to step 916;

Step 914: Set the parameter PA1_overoad=0, and go to step 912;

Step 915: Set the parameter PA2_overoad=0, go to step 916;

Step 916: End the transmitted power difference checking operation.

When the first power amplifying circuit 707 and the second poweramplifying circuit 708 of the signal transceiving module 700 are turnedon (Step 901), the signal transceiving module 700 sets the initialparameters tx_cnt=0, tx_ar_cnt=0, txpow_chk_(1,k-1)=0,txpow_chk_(2,k-1)=0, PA1_overload=0, and PA2_overload=0 (Step 902),wherein the parameter tx_cnt represents if the signal transceivingmodule 700 enters the period of using the first power amplifying circuit707 and/or the second power amplifying circuit 708 to transmit the firsttransmitting signal St7 a and/or the second transmitting signal St7 b,the parameter tx_ar_cnt represents the counting number of thetransmitted uplink sub-frame of the data frame, the parametertxpow_chk_(1,k-1) represents the average transmitted power difference ofthe first power amplifying circuit 707 in transmitting k times of theuplink sub-frame, the parameter txpow_chk_(2,k-1) represents the averagetransmitted power difference of the second power amplifying circuit 708in transmitting k times of the uplink sub-frame, the parameterPA1_overload represents if the first power amplifying circuit 707 isoverloaded, and the parameter PA2_overload represents if the secondpower amplifying circuit 708 is overloaded.

When the outcomes of the monitoring method 800 show that the transmittedpower difference checking operation of the first power amplifyingcircuit 707 should be performed (i.e., the step 816) and/or thetransmitted power difference checking operation of the second poweramplifying circuit 708 should be performed (i.e., the step 818), thefirst switching circuit 705 is controlled to couple the first signalport 703 to the first power amplifying circuit 707, and/or the secondswitching circuit 706 is controlled to couple the second signal port 704to the second power amplifying circuit 708 (i.e., txpw_chk_en=1 in step904). Then, the signal transceiving module 700 enters the averagetransmitted power difference detection (step 905-907). For brevity, thefollowing description focuses on when both of the transmitted powerdifference checking operations of the first power amplifying circuit 707and the second power amplifying circuit 708 should be performed.

In step 905, when the signal transceiving module 700 enters the periodtx_chk_period of using the first power amplifying circuit 707 and thesecond power amplifying circuit 708 to transmit the first transmittingsignal St7 a and the second transmitting signal St7 b respectively(i.e., when tx_cnt=tx_chk_period), the second processing circuit 712controls the first power amplifying circuit 707 and the second poweramplifying circuit 708 to transmit the first transmitting signal St7 ahaving a predetermined power txpow_tar and the second transmittingsignal St7 b having the predetermined power txpow_tar.

Then, in step 906, the first power detector 709 detects the firstdetected power txpow_det₁ corresponding to the first transmitting signalSt7 a, and the second power detector 710 detects the second detectedpower txpow_det₂ corresponding to the second transmitting signal St7 b.The second processing circuit 712 further determines the firsttransmitted power difference txpow_diff₁ between the first detectedpower txpow_det₁ and the predetermined power txpow_tar (i.e.,txpow_det₁-txpow_tar), and determines the second transmitted powerdifference txpow_diff₂ between the second detected power txpow_det₂ andthe predetermined power txpow_tar (i.e., txpow_det₂−txpow_tar). In someexemplary embodiments, Txpow_det may be calibrated to add somecompensation so that twpow_det should be very close to txpow_tar whenantenna is properly connected. In some exemplary embodiments, txpow_detis taken an absolute value for comparison before performing theautoregression to compute txpow_chk.

In step 907, after using the first power amplifying circuit 707 and thesecond power amplifying circuit 708 to transmit the first transmittingsignal St7 a and the second transmitting signal St7 b respectively foroutputting a plurality of the uplink sub-frames, the second processingcircuit 712 determines the average transmitted power differencetxpow_chk_(1,k-1) of the first power amplifying circuit 707 and theaverage transmitted power difference txpow_chk_(2,k-1) of the secondpower amplifying circuit 708 according to the equations ofα·txpow_chk_(1,k-1)+(1−α)txpow_diff₁ andα·txpow_chk_(2,k-1)+(1−α)txpow_diff₂ respectively, wherein 0<α<1.

When the number tx_ar_cnt of the transmitted uplink sub-framestransmitted by the first power amplifying circuit 707 and the secondpower amplifying circuit 708 is larger than a threshold number tx_ar_th(i.e., tx_ar_cnt>tx_ar_th in step 909), the signal transceiving module700 enters the PA overload checking operation (Step 910-915). Then, thesecond processing circuit 712 determines if the average transmittedpower difference txpow_chk_(1,k-1) of the first power amplifying circuit707 is larger than a threshold power difference txpw_diff_th (step 910).If the second processing circuit 712 determines that the averagetransmitted power difference txpow_chk_(1,k-1) is larger than thethreshold power difference txpw_diff_th, the second processing circuit712 determines that the first power amplifying circuit 707 is overloaded(PA1_overload=1 in step 911). Otherwise, the second processing circuit712 determines that the first power amplifying circuit 707 is notoverloaded (PA1_overload=0 in step 914).

The second processing circuit 712 further determines if the averagetransmitted power difference txpow_chk_(2,k-1) of the second poweramplifying circuit 708 is larger than the threshold power differencetxpw_diff_th (step 912). If the second processing circuit 712 determinesthat the average transmitted power difference txpow_chk_(2,k-1) islarger than the threshold power difference txpw_diff_th, the secondprocessing circuit 712 determines that the second power amplifyingcircuit 708 is overloaded (PA2_overload=1 in step 913). Otherwise, thesecond processing circuit 712 determines that the second poweramplifying circuit 708 is not overloaded (PA2_overload=0 in step 915).The transmitted power difference checking operation of the signaltransceiving module 700 is ended (step 916) when both of the overloadconditions of the first power amplifying circuit 707 and the secondpower amplifying circuit 708 are determined.

In addition, according to the outcome of the overload checking upon thefirst power amplifying circuit 707 and the second power amplifyingcircuit 708, the second processing circuit 712 further performs thepower protection scheme 1000 to control operations of the first poweramplifying circuit 707 and the second power amplifying circuit 708according to the parameters PA1_overload PA2_overload as shown in FIG.10. FIG. 10 is a diagram illustrating the power protection scheme 1000performed by the signal transceiving module 700 according to anembodiment of the present invention. Provided that substantially thesame result is achieved, the steps of the flowchart shown in FIG. 10need not be in the exact order shown and need not be contiguous; thatis, other steps can be intermediate. The power protection scheme 1000comprises the following steps:

Step 1001: Start;

Step 1002: Determine if the parameter PA1_overload is 1; if yes, go tostep 1003, if no, go to step 1005;

Step 1003: Determine if the parameter OFF_PA1 is 1; if yes, go to step1004, if no, go to step 1006;

Step 1004: Turn off the first power amplifying circuit 707, go to step1008;

Step 1005: Turn on the first power amplifying circuit 707, go to step1008;

Step 1006: Determine if txpow_tar>pw_max−pw_dw; if yes, go to step 1007,if no, go to step 1008;

Step 1007: Set txpow_p1 as pw_max−pw_dw;

Step 1008: Determine if the parameter PA2_overload is 1; if yes, go tostep 1009, if no, go to step 1011;

Step 1009: Determine if the parameter OFF_PA2 is 1; if yes, go to step1010, if no, go to step 1012;

Step 1010: Turn off the second power amplifying circuit 708, go to step1014;

Step 1011: Turn on the second power amplifying circuit 708, go to step1014;

Step 1012: Determine if txpow_tar>(pw_max−pw_dw); if yes, go to step1013, if no, go to step 1014;

Step 1013: Set txpow_p2 as pw_max−pw_dw;

Step 1014: End the power protection scheme 1000.

When the PA overload checking operation (Step 910-915) is performed, thesecond processing circuit 712 (which may be controlled by the firstprocessing circuit 711) checks the outcome of the parameter PA1_overloadto determines if the first power amplifying circuit 707 is overloaded(Step 1002). When the first power amplifying circuit 707 is overloaded,and when the first power amplifying circuit 707 is not to be used in thenormal operation of the signal transceiving module 700, i.e., whenOFF_PA1=1, the second processing circuit 712 stops the first poweramplifying circuit 707 from generating the transmitting signal St7 a.For example, the second processing circuit 712 just turns off the firstpower amplifying circuit 707 (Step 1004). However, when the first poweramplifying circuit 707 is overloaded, and when the first poweramplifying circuit 707 is to be used in the normal operation of thesignal transceiving module 700, the second processing circuit 712determines if the power txpow_tar to be transmitted by the first poweramplifying circuit 707 is larger than the predetermined power level,wherein the predetermined power level is a power level lower than themaximum power pw_max of the first power amplifying circuit 707 by apredetermined power range pw_dw, i.e., pw_max−pw_dw. When the secondprocessing circuit 712 determines that the power txpow_tar to betransmitted by the first power amplifying circuit 707 is larger than thepredetermined power level, i.e., txpow_tar>pw_max−pw_dw, the secondprocessing circuit 712 sets the maximum power txpow_p1 to be transmittedby the first power amplifying circuit 707 as the predetermined powerlevel, i.e., pw_max−pw_dw.

In addition, the second processing circuit 712 checks the outcome of theparameter PA2_overload to determine if the second power amplifyingcircuit 708 is overloaded (Step 1008). When the second power amplifyingcircuit 708 is overloaded, and when the second power amplifying circuit708 is not to be used in the normal operation of the signal transceivingmodule 700, i.e., when OFF_PA2=1, the second processing circuit 712stops the second power amplifying circuit 708 from generating thetransmitting signal St7 b. For example, the second processing circuit712 just turns off the second power amplifying circuit 708 (Step 1010).However, when the second power amplifying circuit 708 is overloaded, andwhen the second power amplifying circuit 708 is to be used in the normaloperation of the signal transceiving module 700, the second processingcircuit 712 determines if the power txpow_tar to be transmitted by thesecond power amplifying circuit 708 is larger than the predeterminedpower level, wherein the predetermined power level is a power levellower than the maximum power pw_max of the second power amplifyingcircuit 708 by a predetermined power range pw_dw, i.e., pw_max−pw_dw.When the second processing circuit 712 determines that the powertxpow_tar to be transmitted by the second power amplifying circuit 708is larger than the predetermined power level, i.e.,txpow_tar>pw_max−pw_dw, the second processing circuit 712 sets themaximum power txpow_p2 to be transmitted by the second power amplifyingcircuit 708 as the predetermined power level, i.e., pw_max-pw_dw. Theadvantage of OFF_PA=1 is the operation mode which turn-off the PA, andit not only protect the PA, but also save some transmission power. Theadvantage of OFF_PA=0, it just transmits less power to protect the PAfrom overloading. Thus, the mode of OFF_PA=0 could have bettertransmission performance with the cost of more PA power compared withOFF_PA=1 mode.

In steps 1002 and 1008, when the first power amplifying circuit 707 andthe second power amplifying circuit 708 are not overloaded, the secondprocessing circuit 712 simply turns on the first power amplifyingcircuit 707 and the second power amplifying circuit 708 (steps 1005 and1011).

Therefore, by controlling the power amplifying circuit having an antennathat is not coupled to its signal port correctly to stop generate thetransmitting signal, or limiting the maximum power of the transmittedsignal to the predetermined power level, the power amplifying circuitcan be prevented from burning out or deterioration.

Please refer to FIG. 11. FIG. 11 is a timing diagram illustrating a dataframe 1100 received and transmitted by the signal transceiving module700 according to an embodiment of the present invention. The data frame1100 comprises a receive transition gap (RTG), a downlink (DL)sub-frame, a transmit transition gap (TTG), a uplink (UL) sub-frame.According to the embodiment, the monitoring operation (i.e., themonitoring method 800) is performed in a time interval T3 when thedownlink sub-frame is received. Based on the outcome of the monitoringoperation, the transmitted power difference checking operation (i.e. thetransmitted power difference checking method 900) is performed in a timeinterval T4 when the uplink sub-frame is transmitted. Then, based on theoutcome of the transmitted power difference checking operation, thepower protection scheme 1000 is performed before the transmission of theuplink sub-frame, i.e., in a time interval T5 of the transmit transitiongap.

Briefly, according to the present invention, it can be determinedwhether an antenna is coupled to a corresponding signal port correctly,wherein some of the preferred embodiments are arranged to detect asignal quality of a received signal to determine if an antenna iscoupled to the corresponding signal port correctly, and some of thepreferred embodiments are arranged to detect a signal quality of areceived signal in conjunction with a power difference between adetected power and the transmitted power of a transmitted signal todetermine if an antenna is coupled to the corresponding signal portcorrectly. Then, by controlling the power amplifying circuit having anantenna that is not coupled to its signal port correctly to stopgenerating the transmitting signal, by or limiting the maximum power ofthe transmitted signal to the predetermined power level, the poweramplifying circuit can be prevented from burning out or deterioration.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the invention. Accordingly, the abovedisclosure should be construed as limited only by the metes and boundsof the appended claims.

1. A signal transceiving module, comprising: a first antenna; a firstsignal port; and a first processing circuit, coupled to the first signalport and arranged to detect a first signal quality of a first receivedsignal received from the first signal port and determine if the firstantenna is coupled to the first signal port correctly according to atleast the first signal quality.
 2. The signal transceiving module ofclaim 1, wherein when the first processing circuit detects that thefirst signal quality is lower than a predetermined quality level, thefirst processing circuit determines that the first antenna is notcoupled to the first signal port correctly.
 3. The signal transceivingmodule of claim 2, further comprising: a first power amplifying circuit,coupled to the first signal port and arranged to generate a transmittingsignal; wherein when the first processing circuit detects that the firstantenna is not coupled to the first signal port correctly, the firstprocessing circuit further stops the first power amplifying circuit fromgenerating the transmitting signal.
 4. The signal transceiving module ofclaim 2, further comprising: a first power amplifying circuit, coupledto the first signal port and arranged to generate a transmitting signal;wherein when the first processing circuit detects that the first antennais not coupled to the first signal port correctly, the first processingcircuit further limits a maximum power of the transmitting signal to apredetermined power level.
 5. The signal transceiving module of claim 1,wherein when the first processing circuit detects that the first signalquality is higher than a predetermined quality level, the firstprocessing circuit determines that the first antenna is coupled to thefirst signal port correctly.
 6. The signal transceiving module of claim1, wherein when the first processing circuit detects that the firstsignal quality is higher than a predetermined quality level, the firstprocessing circuit stops detecting the first signal quality of the firstreceived signal.
 7. The signal transceiving module of claim 1, whereinthe first signal quality of the first received signal is a receivedsignal strength indication (RSSI), a physical carrier tointerference-plus-noise ratio (PCINR), or a signal-to-noise (SNR) of thefirst received signal.
 8. The signal transceiving module of claim 1,further comprising: a second antenna; and a second signal port; whereinthe first processing circuit is further coupled to the second signalport and arranged to detect a second signal quality of a second receivedsignal received from the second signal port, and the first processingcircuit determines if the first antenna is coupled to the first signalport correctly and the second antenna is coupled to the second signalport correctly according to the first signal quality and the secondsignal quality.
 9. The signal transceiving module of claim 8, whereinwhen the first processing circuit detects that the first signal qualityand the second signal quality are both lower than a predeterminedquality level, the first processing circuit performs a physical carrierto interference-plus-noise ratio (PCINR) checking operation upon thefirst received signal and the second received signal to check if thefirst antenna and the second antenna are respectively coupled to thefirst signal port and the second signal port correctly, and when thefirst processing circuit detects that at least one of the first signalquality and the second signal quality is not lower than thepredetermined quality level, the first processing circuit performs areceived signal strength indication (RSSI) checking operation upon thefirst received signal and the second received signal to check if thefirst antenna and the second antenna are respectively coupled to thefirst signal port and the second signal port correctly.
 10. The signaltransceiving module of claim 9, wherein when the first processingcircuit detects that the first signal quality and the second signalquality are both lower than the predetermined quality level, the firstprocessing circuit subtracts a physical carrier tointerference-plus-noise ratio of the first received signal from aphysical carrier to interference-plus-noise ratio of the second receivedsignal to check if a difference is larger than a first threshold, and tocheck if the physical carrier to interference-plus-noise ratio of thefirst received signal is smaller than a second threshold; and when thedifference is larger than the first threshold and the physical carrierto interference-plus-noise ratio of the first received signal is smallerthan the second threshold, the first processing circuit determines thatthe first antenna is not coupled to the first signal port correctly. 11.The signal transceiving module of claim 9, wherein when the firstprocessing circuit detects that at least one of the first signal qualityand the second signal quality is not lower than the predeterminedquality level, the first processing circuit subtracts a received signalstrength indication of the first received signal from a received signalstrength indication of the second received signal to check if adifference is larger than a threshold; and when the difference is largerthan the threshold, the first processing circuit determines that thefirst antenna is not coupled to the first signal port correctly.
 12. Thesignal transceiving module of claim 1, further comprising: a poweramplifying circuit; a switching circuit, arranged to selectively couplethe first signal port to the first processing circuit or the poweramplifying circuit, wherein when the first processing circuit determinesthat the first antenna is not coupled to the first signal portcorrectly, the switching circuit couples the first signal port to thepower amplifying circuit; a second processing circuit, coupled to thepower amplifying circuit, the second processing circuit arranged tocontrol the power amplifying circuit to output a transmitting signalhaving a first predetermined power level to the first signal port whenthe power amplifying circuit is coupled to the first signal port; and apower detector, coupled to the second processing circuit and arranged todetect a power level at the first signal port when the power amplifyingcircuit outputs the transmitting signal; wherein the second processingcircuit further determines if the power amplifying circuit is coupled tothe first antenna correctly according to a power difference between thepower level and the first predetermined power level.
 13. The signaltransceiving module of claim 12, wherein when the second processingcircuit detects that the power amplifying circuit is not coupled to thefirst antenna correctly and the power amplifying circuit is not to beused in a normal operation of the signal transceiving module, the secondprocessing circuit further stops the power amplifying circuit fromgenerating the transmitting signal.
 14. The signal transceiving moduleof claim 12, wherein when the second processing circuit detects that thepower amplifying circuit is not coupled to the first antenna correctlyand the power amplifying circuit is to be used in a normal operation ofthe signal transceiving module, the second processing circuit furtherlimits a maximum power of the transmitting signal to a secondpredetermined power level.
 15. The signal transceiving module of claim12, wherein when the second processing circuit detects that the powerdifference is not larger than a predetermined power difference level,the second processing circuit determines that the power amplifyingcircuit is coupled to the first antenna correctly.
 16. The signaltransceiving module of claim 12, wherein when the second processingcircuit detects that the power difference is not larger than apredetermined power difference level, the second processing circuitstops determining if the power amplifying circuit is coupled to thefirst antenna correctly.